A sandwich.
A kind of sandwich made in a long loaf of bread.
Any submarine plant or animal.
A boat that can go underwater.
A pitch delivered with an underhand motion.
A stowaway on a seagoing vessel.
To sink or submerge oneself.
To torpedo; to destroy with a sudden sneak attack.
To operate or serve on a submarine.
To slide forwards underneath one's seat belt (during a crash or sudden stop).
Existing, relating to, or made for use beneath the sea.
Hidden or undisclosed.
Of a pitch, thrown with the hand lower than the elbow.